Do Now Predict why weather could be different on the front side of a mountain (windward) than on the back side of the mountain (Leeward). Explain.

Weather Factors

Types of Fronts and How they Form

front – the area where the air masses meet and do not mix There are 4 types of fronts: Cold fronts Warm fronts Stationary fronts Occluded fronts

Cold Front cold front - cold air moves in under a warm air mass What kind of weather would you expect a cold front to produce? Cold fronts can produce short, heavy rains, often thunderstorms with heavy winds, followed by clear skies and cooler, drier weather.

Warm Front warm front – warm air moves in over a cold air mass What kind of weather does a warm front produce? A warm front can cause steady rain or snow that may last for days and light winds, followed by warmer and more humid weather.

Stationary Front stationary front – an unmoving front where a cold air mass and a warm air mass meet

Occluded Front occluded front – a front formed where a warm front and cold front meet

What Do Fronts Look Like from Space? Satellites show large weather patterns, such as fronts and storms which help weather scientists.

WIND

Wind Currents Wind currents help distribute the sun’s heat from one part of the world to another. Warmer air has lower pressure than cooler air. The cooler air rushes into the low pressure areas causing wind. Warm air currents make areas warmer than normal. Cold air currents make areas cooler than normal High Pressure Air Low Pressure Air Wind blows from areas of High Pressure to Low Pressure

A wind is the horizontal movement of air from an area of high pressure to an area of low pressure. All winds are caused by differences in air pressure.

local winds – winds that blow over short distances Local winds are caused by unequal heating of Earth’s surface within a small area. sea breeze – a wind that blows from an ocean or lake onto land land breeze – the flow of air from land to a body of water

Global Winds global winds – winds that blow steadily from specific directions over long distances The movement of air between the equator and the poles produces global winds. Coriolis Effect – the way Earth’s rotation makes winds curve

- Winds Coriolis Effect As Earth rotates, the Coriolis effect turns winds in the Northern Hemisphere toward the right.

Precipitation

precipitation – any form of water that falls from clouds and reaches Earth’s surface Common types of precipitation include: Rain Sleet Freezing rain Hail Snow

evaporation – the process by which water molecules in liquid water escape into the air as water vapor

Convection process

How Clouds Form - Water in the Atmosphere Clouds form when warm, moist air rises and cools. Water vapor condenses on tiny particles to form liquid water or ice crystals.

In your journal create a sketch map of the water cycle

Topography - Elevation Elevation is the height above sea level The higher the elevation of a region the cooler the temperature becomes. Cooler Temperatures Warmer Temperatures

Topography – Rain Shadows Mountains can create orographic rainfall. The windward side of the mountain is rainy while the leeward side is very dry. Rain Shadows are desert regions created on the leeward side of the mountain Which side is the leeward side, the right or the left? Windward Which side is the windward side, the right or the left?

Closing Compare your sketch of the orographic cycle with your shoulder partner. Help each other fill in important information.